Research and development on apparatuses that automatically control steering, an accelerator, and a brake of a vehicle in order to detect a dangerous event around the vehicle and in order to avoid the detected dangerous event, has been conducted for achievement of safe traveling of vehicles. Some of the vehicles have been already equipped with the apparatuses. A system that detects an obstacle, such as a vehicle or a pedestrian, in the front of a vehicle with a camera with which the vehicle has been equipped, and then alerts to a driver or applies an automatic brake, in the apparatuses is effective in terms of improvement of safety of the vehicle.
In a system that detects an obstacle around a motor vehicle from an image of a camera with which the motor vehicle has been equipped, the number of types of objects to be detected tends to increase. Thus, there is a need to detect a plurality of objects simultaneously. PTL 1 describes a method of performing processing for detecting a plurality of objects on a time series basis with one image sensor shared, in order to meet the need. There is a need to perform detection processing with a limited calculation resource amid a tendency to increase image data to be processed due to an increase of the number of pixels of a camera. PTL 2 describes a method of performing processing by extracting an image region necessary for detecting each object as a method of meeting the need.